net: lan966x: Add support for XDP_TX

Extend lan966x XDP support with the action XDP_TX. In this case when the
received buffer needs to execute XDP_TX, the buffer will be moved to the
TX buffers. So a new RX buffer will be allocated.
When the TX finish with the frame, it would give back the buffer to the
page pool.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
index bc30c31..cd62231 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
@@ -410,12 +410,17 @@ static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
                dcb_buf->dev->stats.tx_bytes += dcb_buf->len;
 
                dcb_buf->used = false;
-               dma_unmap_single(lan966x->dev,
-                                dcb_buf->dma_addr,
-                                dcb_buf->len,
-                                DMA_TO_DEVICE);
-               if (!dcb_buf->ptp)
-                       dev_kfree_skb_any(dcb_buf->skb);
+               if (dcb_buf->use_skb) {
+                       dma_unmap_single(lan966x->dev,
+                                        dcb_buf->dma_addr,
+                                        dcb_buf->len,
+                                        DMA_TO_DEVICE);
+
+                       if (!dcb_buf->ptp)
+                               napi_consume_skb(dcb_buf->data.skb, weight);
+               } else {
+                       xdp_return_frame_rx_napi(dcb_buf->data.xdpf);
+               }
 
                clear = true;
        }
@@ -548,6 +553,9 @@ static int lan966x_fdma_napi_poll(struct napi_struct *napi, int weight)
                        lan966x_fdma_rx_free_page(rx);
                        lan966x_fdma_rx_advance_dcb(rx);
                        goto allocate_new;
+               case FDMA_TX:
+                       lan966x_fdma_rx_advance_dcb(rx);
+                       continue;
                case FDMA_DROP:
                        lan966x_fdma_rx_free_page(rx);
                        lan966x_fdma_rx_advance_dcb(rx);
@@ -669,6 +677,62 @@ static void lan966x_fdma_tx_start(struct lan966x_tx *tx, int next_to_use)
        tx->last_in_use = next_to_use;
 }
 
+int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
+                          struct xdp_frame *xdpf,
+                          struct page *page)
+{
+       struct lan966x *lan966x = port->lan966x;
+       struct lan966x_tx_dcb_buf *next_dcb_buf;
+       struct lan966x_tx *tx = &lan966x->tx;
+       dma_addr_t dma_addr;
+       int next_to_use;
+       __be32 *ifh;
+       int ret = 0;
+
+       spin_lock(&lan966x->tx_lock);
+
+       /* Get next index */
+       next_to_use = lan966x_fdma_get_next_dcb(tx);
+       if (next_to_use < 0) {
+               netif_stop_queue(port->dev);
+               ret = NETDEV_TX_BUSY;
+               goto out;
+       }
+
+       /* Generate new IFH */
+       ifh = page_address(page) + XDP_PACKET_HEADROOM;
+       memset(ifh, 0x0, sizeof(__be32) * IFH_LEN);
+       lan966x_ifh_set_bypass(ifh, 1);
+       lan966x_ifh_set_port(ifh, BIT_ULL(port->chip_port));
+
+       dma_addr = page_pool_get_dma_addr(page);
+       dma_sync_single_for_device(lan966x->dev, dma_addr + XDP_PACKET_HEADROOM,
+                                  xdpf->len + IFH_LEN_BYTES,
+                                  DMA_TO_DEVICE);
+
+       /* Setup next dcb */
+       lan966x_fdma_tx_setup_dcb(tx, next_to_use, xdpf->len + IFH_LEN_BYTES,
+                                 dma_addr + XDP_PACKET_HEADROOM);
+
+       /* Fill up the buffer */
+       next_dcb_buf = &tx->dcbs_buf[next_to_use];
+       next_dcb_buf->use_skb = false;
+       next_dcb_buf->data.xdpf = xdpf;
+       next_dcb_buf->len = xdpf->len + IFH_LEN_BYTES;
+       next_dcb_buf->dma_addr = dma_addr;
+       next_dcb_buf->used = true;
+       next_dcb_buf->ptp = false;
+       next_dcb_buf->dev = port->dev;
+
+       /* Start the transmission */
+       lan966x_fdma_tx_start(tx, next_to_use);
+
+out:
+       spin_unlock(&lan966x->tx_lock);
+
+       return ret;
+}
+
 int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev)
 {
        struct lan966x_port *port = netdev_priv(dev);
@@ -724,7 +788,8 @@ int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev)
 
        /* Fill up the buffer */
        next_dcb_buf = &tx->dcbs_buf[next_to_use];
-       next_dcb_buf->skb = skb;
+       next_dcb_buf->use_skb = true;
+       next_dcb_buf->data.skb = skb;
        next_dcb_buf->len = skb->len;
        next_dcb_buf->dma_addr = dma_addr;
        next_dcb_buf->used = true;

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
index 42be5d0..0b77073 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
@@ -302,13 +302,13 @@ err:
        return NETDEV_TX_BUSY;
 }
 
-static void lan966x_ifh_set_bypass(void *ifh, u64 bypass)
+void lan966x_ifh_set_bypass(void *ifh, u64 bypass)
 {
        packing(ifh, &bypass, IFH_POS_BYPASS + IFH_WID_BYPASS - 1,
                IFH_POS_BYPASS, IFH_LEN * 4, PACK, 0);
 }
 
-static void lan966x_ifh_set_port(void *ifh, u64 bypass)
+void lan966x_ifh_set_port(void *ifh, u64 bypass)
 {
        packing(ifh, &bypass, IFH_POS_DSTS + IFH_WID_DSTS - 1,
                IFH_POS_DSTS, IFH_LEN * 4, PACK, 0);

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
index 81c0b11..3c18fce 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
@@ -105,11 +105,13 @@ enum macaccess_entry_type {
  * FDMA_PASS, frame is valid and can be used
  * FDMA_ERROR, something went wrong, stop getting more frames
  * FDMA_DROP, frame is dropped, but continue to get more frames
+ * FDMA_TX, frame is given to TX, but continue to get more frames
  */
 enum lan966x_fdma_action {
        FDMA_PASS = 0,
        FDMA_ERROR,
        FDMA_DROP,
+       FDMA_TX,
 };
 
 struct lan966x_port;
@@ -175,10 +177,14 @@ struct lan966x_rx {
 struct lan966x_tx_dcb_buf {
        dma_addr_t dma_addr;
        struct net_device *dev;
-       struct sk_buff *skb;
+       union {
+               struct sk_buff *skb;
+               struct xdp_frame *xdpf;
+       } data;
        u32 len;
        u32 used : 1;
        u32 ptp : 1;
+       u32 use_skb : 1;
 };
 
 struct lan966x_tx {
@@ -360,6 +366,8 @@ bool lan966x_hw_offload(struct lan966x *lan966x, u32 port, struct sk_buff *skb);
 
 void lan966x_ifh_get_src_port(void *ifh, u64 *src_port);
 void lan966x_ifh_get_timestamp(void *ifh, u64 *timestamp);
+void lan966x_ifh_set_bypass(void *ifh, u64 bypass);
+void lan966x_ifh_set_port(void *ifh, u64 bypass);
 
 void lan966x_stats_get(struct net_device *dev,
                       struct rtnl_link_stats64 *stats);
@@ -460,6 +468,9 @@ u32 lan966x_ptp_get_period_ps(void);
 int lan966x_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts);
 
 int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev);
+int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
+                          struct xdp_frame *frame,
+                          struct page *page);
 int lan966x_fdma_change_mtu(struct lan966x *lan966x);
 void lan966x_fdma_netdev_init(struct lan966x *lan966x, struct net_device *dev);
 void lan966x_fdma_netdev_deinit(struct lan966x *lan966x, struct net_device *dev);

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
index ba7aa6d..8996110 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
@@ -54,6 +54,7 @@ int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
 {
        struct bpf_prog *xdp_prog = port->xdp_prog;
        struct lan966x *lan966x = port->lan966x;
+       struct xdp_frame *xdpf;
        struct xdp_buff xdp;
        u32 act;
 
@@ -66,6 +67,13 @@ int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
        switch (act) {
        case XDP_PASS:
                return FDMA_PASS;
+       case XDP_TX:
+               xdpf = xdp_convert_buff_to_frame(&xdp);
+               if (!xdpf)
+                       return FDMA_DROP;
+
+               return lan966x_fdma_xmit_xdpf(port, xdpf, page) ?
+                      FDMA_DROP : FDMA_TX;
        default:
                bpf_warn_invalid_xdp_action(port->dev, xdp_prog, act);
                fallthrough;